Control mechanism for motor operated chairs and the like



Sept 8, 1953 N. E. LAUTERBACH 2,653

CONTROLv MECHANISM FOR MOTOR OPERATED CHAIRS Filed June 27, 1947 AND THE LIKE 5 Sheets-Sheet 1 INVENTOR. NORM/4N6 MU/TAIQACH ep 1953 N. E. LAUTERBACH 265L351 CONTROL MECHANISM FOR M Filed June 27, 1947 OTOR OPERATED CHAIRS AND THE LIKE 5 Sheets-Shea; 2

p 3 N. E. LAUTERBACH 2,651,353

CONTROL [MECHANISM FOR MOTOR OPERATED CHAIRS AND THE LIKE Filed June 2'7, 1947 5 Sheets-Sheet 3 m fie J.

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INVENTOR. NORMA/V15 Muff/EACH B if sepia 1953 N. E. LAUTERBACH 2,651,353

CONTROL MECHANISM FOR MOTOR OPERATED CHAIRS AND THE LIKE Filed June 27, 1947 5 Sheets-Sheet 4 INVENTOR. NORMA/V f. ZAU/ZABACH HASATTO/QA/EY LIKE CONTROL MECHANISM FOR MOTOR OPERATED CHAIRS AND THE 5 SheetsSheet 5 Filed June 27, 1947 INVENTOR. NORA/ANZ'TZAUTf/FBAC/v HAS ATTORNEY Patented Sept. 8, 1953 CONTROL MECHANISM FOR MOTOR OPERATED CHAIRS AND THE LIKE Norman E. Lauterbach, Newark, N. Y., assignor to Ritter Company, Inc.

poration of Delaware Rochester, N Y., a 00].!

Application June 27, 1947, Serial No. 757,513

9 Claims. '1

This inventionrelates to motor-operated chairs such as employed in dental and other medical practice and the like, one object of the invention being to provide an improved chair of this character having .a more simple, practical and convenient control mechanism for the circuit of the motor for operating the elevating mechanism of the chair. Another object is the provision of such .a chair having a more adaptable and efricient construction in which a controlling pedal means alone may be shifted to diiferent positions around the chair to suit the convenience of the operator, independently of the positions of the motor, elevating mechanism and seat frame of the chair.

Another object is to provide .a chair of the above character comprisingpedal means movable simultaneously to different positions about the chair for controlling the chair motor circuit and also an auxiliary electric circuit such, for em ample, as the motor circuit of .a dental engine employed in conjunction with the chair.

Still a further object is the provision of improved mechanism having theaoove advantages in a practical form of construction requiring relatively few parts of a simple naturecapable of being readily manufactured and applied with little change in existing chair designs.

To these and other ends the invention resides in certain improvements and combinations of parts a'll .as will be hereinafter .more fully described, the ,novel features being pointed out in the claims at the end of the specification.

In the drawings:

Fig. 1 is aside elevation of thebase and the casing for the ,motor operated parts of a chair embodying the present invention, some of the casing beinglshown in section to expose the pedal control means;

Fig.2 is a top plan view of the parts shown in Fig. ,l partly broken away and with parts of the casing removed for better illustration;

Fig. .3 is an enlarged sectional elevation of .a portion of the pedal .means, substantially on the line .33 in Fig. :2;

Fig. 4 is a view similar .toFig. 3 of other parts of the pedal means, substantially on the line 44 in Fig- 2;

Fig. 5iisaffragmentary elevationof spring centering means, substantially as seen from the line 5-5 .in vFig. 2;

Fig. -6 .is an enlarged elevation of additional pedal means, substantially on the line 6-6 in F g- '2;

Fig. 7 isa-fragmentaryside elevation, as viewed 2 from the line 'l-p'l;i n,Fig. 8 andshowing a modified form of construction, and

Fig. .8 is a top plan view similar to Fig. v2 but illustrating the modified construction shown in Fig. .7.

Motor operated chairs such, for example, as employed in the practice of dentistry, have commonly comprised a stationary supporting base on which the motor, ,motor operated elevating mechanism and chair frame have been mounted for rotary adjustment to suitably position the chair frame with relation to other equipment, such as a dental equipment stand or dental engine, to dispose them within convenient reach for use by the operator on the occupant of the chair. In such positions ,of the chair, the motor controlling ,pedal means for raising and lowering it have not been always located within convenient reach of the operators toe and the pedals could only be adjusted by movement of the operator about the chair to the established pedal location. Moreover, the control means for the dental engine used in conjunction with the chair has usually been a separate and detached and somewhat unstable, foot operated device slidably resting on the floor in haphazard position.

I have found that such motor operated chairs can be materially improved and the above dif- 9. ficulties overco e by a-construction in which the pedal means alone are movably mounted on the stationary base for adjustment therearound to positions on diiferent sides thereof to suit the convenience of the operator, with connections from the pedal means to the chair operating motor, or other circuits to be controlled such as the :motor circuit of the dental engine employed adjacent the chair, the pedal control means being adjustable to any convenient positionadjacent that occupied by the operator, reardless of the position-of the chair.

Referring more particularly to the drawings, the invention is shown in the present instance, by Way of illustration, as applied to a chair base it of circular shape, adapted to rest upon and be suitably secured to the floor. Risingrrom the center of the .base is a cylindrical column H (Fig. 1) ofintegralorother substantial construction, for supporting the chair operating motor and the elevating mechanism for actuating the usual raising tube l2, to the top of which the chair frame (notshown) is rotatably or fixedly secured as desired. The motor is :housed in an auxiliary casing l3, secured to a side of the column 1;] and the motor actuated mechanism i (not shown) for raising and lowering the tube l2 chair frame may have any known or suitable construction, such as a mechanism of the known hydraulic type, as Well understood in the art. A relatively light auxiliary casing is is preferably provided to enclose and conceal column ii, motor casing 53 and the pedal mechanism hereafter described.

Column l l is provided with a flange (Fig. 4) projecting laterally outwardly a short distance above the base i B, the upper surface of the flange being formed with a ball race l5 providing a guideway extending around the column H for an adjustable ring indicated generally at H. Ring ll has a vertically extending cylindrical body portion is and an inwardly extending flange l9, these parts being so dimensioned as to conform generally to and overlie the column flange I5. That is, ring flange l9 overlies flange l5 and extends inwardly adjacent the Wall of the column, while the vertical body portion iii of the ring depends adjacent to and below the periphery of the column flange l5, as shown. Body portion iii of the ring preferably extends somewhat above the flange l9, so as to provide a projecting shoulder 28, for a purpose hereafter described. The under surface of flange I9 is formed with a ball race 2! for a series of ball elements 22 supported in the race E6 of the column flange l5, so that ring ll is supported to rotate on flange l5 concentrically with the column ii.

The means for supporting the controlling pedal means comprises, preferably, a carriage indicated generally at 23 (Figs. 1 and 4) having an arcuate shape concentric with the column I l and formed at its top with a flange 25 extending inwardly over the shoulder 25 of ring H. The under surface of flange 25 is recessed or grooved, as at 25, to slidably engage shoulder 25! and retain the carriage on the ring for adjustment to different positions around the chair. The carriage comprises a vertically depending wall portion 25, having its central portion cut away as at Zl, for a purpose hereafter described. Thi wall portion is provided, adjacent the center of its lower outer edge, with a pair of spaced lugs 28, between which is pivoted a locking lever 29 (Fig. 6). The lever is formed at its inner end with a hub portion at, Fig. 2, carrying laterally projecting trunnion screws 3i rotating in bearing openings in the lugs Extending centrally through the hub is a set screw 32, the adjustably projecting lower end of which bears against one end of a leaf spring 33 fixed at its other end to the bottom of the carriage, so that the pedal is yieldably retained in either a raised or lowered position to which it may be moved. The hub of lever 29 has its inner side formed in the shape of a cam St, for engagement with a depending arm 35 of a bell crank lever 35 pivotally mounted on a pintle ill supported at its ends in the lugs 28. The other arm 38 of the bell crank extends inwardly through the opening 2i in the carriage, in position to engage the lower edge of ring ll.

It will be evident from this construction that when pedal 29 is raised to the full line position shown in Figs. 1 and 6, its cam face 34 releases bell crank 35 so that its heavier inner arm 38 drops clear of the lower edge of ring ll, thus freeing the carriage for sliding adjustment circumferentially of the ring, the pedal being retained in this released position by spring 33. When pedal 29 is depressed to the dotted line position, however, the inner arm 38 of the bell crank is cammed upwardly into gripping engagement with the lower edge of the ring, so as to lock the carriage to the ring, after which movement of the carriage, by lateral pressure against pedal 25, operates to move the ring around the column ii, the pedal being retained in such locking position by spring 33 and the friction between the parts.

The pedal means for controlling the motor and its driven mechanism for raising and lowering the seat frame comprise a pair of pedals, 39 and 55, mounted at the bottom of the opposite end of carriage 23. Pedal (Fig. 4) for raising the chair seat frame is pivoted at ll between a pair of spaced lugs 52 on the carriage and has an upwardly extending arm 43, to the opposite sides of which are attached, as at 44, the opposite ends of a flexible element 55, preferably a roller sprocket chain of known construction, which is slidably supported in a groove 16 formed circumferentially in the upper half of the outer face of the ring H. Chain 55 passes outwardly around one end of carriage 23 for connection with pedal arm 53 from the other side of which it passes back through the carriage opening 2'! and it is connected with one of the devices for controlling the motor, as hereafter described. Pedal arm 53 carries a set screw A l locked by a nut 48 and arranged to bear at its inner end against the carriage wall, to limit the inward movement of the pedal arm under the tension of the chain.

The other pedal for lowering the chair seat frame is similarly pivoted between lugs 49 (Fig. 3) on the other end of the carriage and has a short upwardly extending arm 50, to the opposite sides of which are fixed, as at lit, the opposite ends of a flexible element or chain 52, such as described above, slidably supported in a similar groove 53 in the lower half of the outer face of ring [1. Chain 52 is connected with the other control device of the raising and lowering mechanism, as hereafter described. Arm 5!! of pedal All carries a set screw 54, similar to that of pedal 39, for limiting its inward movement. A number of spaced brackets 54a (Fig. 6), are preferably fixed to the inner surface of ring H, as shown, in position to engage the under side of flange l5 and prevent the ring from being cocked out of a horizontally level position by foot pressure applied to any of the pedals.

Chain extends outwardly from its supporting groove in ring I? to pass around an idler sprocket 55 (Figs. 1 and 2) on a slide 56 movable longitudinally in a bearing in a stationary post 51 on the base It. The outer end of the slide has a flange 58 extending oppositely therefrom, its upwardly extending portion being arranged to engage an actuating plunger 59 of a switch Gil for starting the operation of the motor for raising the seat frame. Switch 60 may have any known or suitable construction in which plunger 59 is spring actuated outwardly to open the switch, except when pressed inwardly by flange 58. This flange and the slide are normally moved outwardly by spring means 6! interposed between the lower portion of the flange and post 51, so as to normally tension chain 45, and raise pedal 39, with the switch in open position. Depression of the pedal moves its upwardly extending arm 43 outwardly to pull the chain outwardly from its supporting groove in the ring at the position of the pedal, thereby so tensioning the chain as to pull slide 55 inwardly and close the switch. to start the motor.

For lowering the seat frame, the lower chain 52 passes around an idler sprocket 62 on a slide 63 movable longitudinally in a lower bearing post .5], the outer end of the slide having 19. depending flange 64 with a spring '65 interposed .between it and the post, to normally move the slide outwardly against the tension of the chain. The slide is movably connected with a lever 66 pivoted at 61 on post 5'! and having its opposite end pivotally connected at 68 with :one end of a link 69 leading, for example, to the fluid release valve of an elevating mechanism of the known hydraulic type. The corresponding pedal All is normally held :in raised position by the tension of chain .52 and, when depressed, increases the tension of the chain so as :to pull-slidebB inwardly and move link 69 outwardlyto open the :fiuid release valve and .allow the :seat frame to descend.

Pedal 2-9 is employed, not only .for ,locking the carriage for :all of the pedals in adjusted position, but also for shifting the :ring .1 through a limited distance circumferentially for actuating a controller for an additional electric circuit, such as that of the dental engine :usually emplayed in association with such motor driven chairs. For this purpose, ring 1.! is connected with a controller of known construction :comprising a contact arm 70 (Fig. '2) having a-contact element 'Il 'engageable successively with a seriesof spaced contacts 12 :on an insulating support 13 stationarily supported on the base or .column H of the chair. The ring is normally retained with contact arm l in a neutral central position by resilient limiting means (Figs. 12 and comprising, preferably, a pair of curved leaf springs, I4 and 15, each fixed at one end to a post on the base, as 16 and llyrespectively. The opposite adjacent ends of the springs are fixed at 18 and 19, respectively, to an'arm 80 fixed on ring 11, and it is evident from this construction that the ring may be moved a limited distance in opposite directions against the tension of the springs, as indicated by the dotted'line positions shown in Fig. 2, but that the springs act to :return the ring and contact arm to central position, as shown in 'full lines, when lateral pressure against pedal 29 is released.

It is evident from the above description of the construction and arrangement of the parts that the locking pedal 29 may be kicked upwardly to the position shown in'Fig. 6, thereby unclamping and releasing the carriage for sliding movement on the ring to substantially any desired position around the chair, as the working position and convenience of the operator may 'from time to time require, as indicated by the full-and dotted line positions shown in Fig. 2, independently of any movement of the motor, elevating mechanism, or chair seat frame. During such adjustment of the pedal means, from one position to another about the chair, the roller chains 45 and 52 slide with little frictional resistance 'in their supporting grooves 48 and 53 of the ring and around the sprockets 55 and :62, without affecting the control devices of the elevating mechanism, or the position of the ring or its controller, although, (if desired for greater safety, the controller circuit may be opened by suitable "switch means during such adjustment. When the pedal carriage has thus been suitably located, pedal 29 is pressed downwardly, thereby clamping and locking the carriage to the ring, with the raising and lowering pedal, 39 and 40, respectively, arranged for operation to control the elevation of the seat frame. With the seat frame elevated to the desired position, lateral pressure may be applied to pedal 29 to operate the controller contact arm 10 in either of opposite directions to supply operating current in either direction of polarity and in varying amount as .desired, for example, for controlling the direction and speed of a dental engine, as well understood in the art.

In the modified construction shown in Figs. 7 and 8, the dental engine controller, instead of being associated directly with the chair base, is mounted instead inside the casing 81 (Fig. :8) of a dental equipment stand, of known or suitable construction, positioned for use adjacent the chair, as shown. This controller, indicated generally at '82, has a wiper arm .83 pivoted at '64 .for movement over the contacts 85 connected in the dental engine motor circuit for controlling the direction of rotation and speed of the motor, as well understood in th art. Pivoted to the wiper arm at 86 is one end 87 of a flexible pushpull Wire of known construction passing through and guided by a flexible tube 85 having one end anchored, as at 89, on the casing of the equipment stand. The other end of the tube extends over the base of the chair, being anchored at in a bracket -9l fixed on the column ii of the chair base. The wire -87 has its end '82 pivoted at 93 to "an arm 94 fixed on ring I7. the remaining parts being the same as described above.

It is evident from the above described construction of this modified form of the invention that rotary adjustment of ring ll serves-to push or pull wire or cable 8'l-and correspondingly swing the wiper arm 33, as in the case of the wiper arm 10 described above, so as to control the motor :circuit of the dental engine. The control mechanism of the chair thus operates a circuit controller which may be either locked directly on the chair or at some remote point to which the control mechanism is connected as by means of the push-pull wire 87 or the like.

The invention therefore supplies a motor open ated chair, such, for example, as employed by dentists, with a control carriage which is -conveniently adjustable to anydesired position about the chair, independently of the positions of the other chair parts, the "carriage having assembled on it allof the pedal means for raising and lowering the seat frame of th chair and for opera-ting the controller for a dental engine, and this improvement is accomplished by a construction comprising relatively few parts of comparatively simple design.

The term ?base in the appended claims is intended to include both the floor engaging portion I0 and its upwardly extending column portion H for supporting the chair.

It will thus be seen that the invention aecomplishes its objects and while it has been herein disclosed by reference to the details of preferred embodiments, it is to be understood that such disclosure is intended in an illustrative, rather than a limiting sense, as it is contemplated that various modifications in the construction and arrangement .of the parts will readily occur to those skilled in th art, within the spirit of the invention and the scope of the appended claims.

I claim:

.1. :A chair having a base, a seat frame mounted on said base for adjustment to different eleviations, motor means on said base for raising said seat frame, supporting means mounted on said base for adjustment therearound to positions on difierent sides thereof while said seat frame is stationary at an adjusted elevation thereof, means comprising a member movably mounted on said supporting means for controlling said motor means in any adjusted position of said supporting means, to raise said frame, and means for releasably locking said supporting means in place with said member in a selected operating position.

2. A chair having a base, a seat frame mounted on said base for adjustment to diiierent elevations, motor means in fixed position on said base for raising said seat frame, a movable device for controlling said motor means, supporting means mounted on said base for adjustment therearound to positions on different sides thereof, a flexible element on said base extending adjacent said supporting means in the different positions thereof and connected with said controlling device, and a pedal member on said supporting means having a part engaging said element and adapted to vary the tension of said element in any position of said supporting means, to move said device and control said motor means.

3. A chair having a base, a seat frame mounted on said base for adjustment to different elevations, motor means for raising said seat frame, a movable device for controlling said motor means, a guideway extending around said base, a flexible element on said base substantially coextensive with said guidewa-y and connected with said device, a carriage adjustable on said guide- Way to positions on different sides of said base, and a pedal member on said carriage having a part engaging said element and adapted to vary the tension of said element in any adjusted position of said carriage, to move said device and control said motor means.

4. A chair having a base, a seat frame mounted on said base for adjustment to different elevations, motor means for raising said seat frame, a movable device for controlling said motor actuated means, a guideway extending around said base, a flexible element on said base substantially coextensive with said guideway and connects with said device, a carriage adjustable on said guideway to positions on different sides of said base, a pedal member on said carriage having a part engaging said element and adapted to vary the tension of said element in any adjusted position of said carriage, to move said device and control said motor means, and pedal means for locking said carriage in place with said pedal member in a selected operating position.

5, A chair having a base, a seat frame mounted on said base for adjustment to different elevations, mechanism for raising said seat frame comprising a pair of control devices for said mechanism, a pair of flexible elements supported by and extending continuously around said base and each connected with one of said control devices, a guideway extending around said base, a carriage adjustable on said guideway to positions on different sides of said base, and a pair of pedals movably mounted on said carriage each having a part engaging one of said elements and adapted to varying the tension of said elements, respectively, in any adjusted position of said carriage, to move said devices and control said mechanism.

6. A chair having a base, a seat frame mounted on said base for adjustment to different elevations, mechanism in fixed position on said base for raising said seat frame and comprising movable devices for controlling said mechanism each provided With an idler pinion, a guideway extending around said base, a carriage adjustable on said guideway to different positions around said base, pedals on said carriage, and roller chains supported by and extending around said base, said chains having meshing engagement with said pinions and having their ends connected to said pedals, respectively, for varying the tension of said chains to move said devices and control said mechanism.

7. A chair having a base, a seat frame mounted on said base for adjustment to different elevations, mechanism in fixed position on said base for raising said seat frame comprising movable devices for controlling said mechanism each provided with an idler pinion, a guideway extending around said base, a carriage adjustable on said guideway to different positions around said base, pedals on said carriage, roller chains supported by and extending around said base, said chains having meshing engagement with said pinions and having their ends connected to said pedals, respectively, for varying the tension of said chains to move said devices and control said mechanism, and pedal means on said carriage for locking said carriage in place on said guideway with said pedals in a selected operating position.

8. A chair having a base, a seat frame mounted on said base for adjustment to different elevations, motor means in fixed position on said base for raising said seat frame, a device for controlling said motor means, a guideway extending around said base, a ring having a limited movement on said guideway around said base, a carriage adjustable on said ring to dififerent positions around said base, a pedal on said carriage having a flexible connection with said device for actuating the same in any position of said carriage around said base, and pedal means on said carriage for moving said carriage and ring around said base.

9. A chair having a base, a seat frame mounted on said base for adjustment to different elevations, motor means in fixed position on said base for raising said seat frame, a devic for controlling said motor means, a guideway extending around said base, a ring having a limited movement on said guideway around said base, a carriage adjustable on said ring to different positions around said base, a pedal on said carriage having a flexible connection with said device for actuating the same in any position of said carriage around said base, and pedal means on said carriage for locking said carriage to said ring with said pedal in a selected operating position.

NORMAN E. LAUTERBACH.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,178,733 Koken Apr. 11, 1916 1,228,434 Hedberg June 5, 1917 1,242,109 Koken Oct. 2, 1917 1,534,270 Koken Apr. 2 1, 1925 1,534,790 Koken Apr. 21, 1925 2,440,644 Powell Apr. 27, 1948 2,449,385 Johnson et al Sept. 14, 1948 

